Handling Vulnerabilities

If HSS detects a vulnerability on a server, you need to handle the vulnerability in a timely manner based on its severity and your business conditions to prevent the vulnerability from being exploited by intruders.

Vulnerabilities can be handled in the following ways:

  • Fixing vulnerabilities

    If a vulnerability may harm your services, fix it as soon as possible. For Linux and Windows vulnerabilities, you can let HSS fix them in one-click. Web-CMS vulnerabilities, emergency vulnerabilities, and application vulnerabilities cannot be automatically fixed. Handle them by referring to the suggestions provided on the vulnerability details page.

  • Ignoring vulnerabilities

    Some vulnerabilities are risky only in specific conditions. For example, if a vulnerability can be exploited only through an open port, but the target server does not open any ports, the vulnerability will not harm the server. If you can confirm that a vulnerability is harmless, you can ignore it.

Constraints

  • The following table describes the OSs that have reached their end of life (EOL). HSS does not support automatic vulnerability fixing on these OSs. You are advised to use the OSs in active support.

    Table 1 OSs that have reached EOS

    OS

    Description

    CentOS 8

    It has reached EOL and will no longer maintained. HSS scans them for vulnerabilities based on Red Hat patch notices, but cannot fix them due to the lack of official patches. You are advised to change to the OSs in active support.

    Ubuntu 16.04, 18.04, 22.04

    They have reached EOL and do not support free patch updates. You need to purchase and configure Ubuntu Pro to install upgrade packages, or vulnerability fix will fail.

    Debian 9 and 10

    It has officially reached EOL. No official patches are available. You are advised to change to the OSs in active support.

    Windows 2012 R2

    It has officially reached EOL. No official patches are available. You are advised to change to the OSs in active support.

  • The kernel vulnerabilities on CCE, MRS, and BMS servers cannot be fixed. Fixing them may make some functions unavailable.

  • To handle vulnerabilities on a server, ensure the server is in the Running state, its agent status is Online, and its protection status is Protected.

Precautions

  • Vulnerability fixing operations cannot be rolled back. If a vulnerability fails to be fixed, services will probably be interrupted, and incompatibility issues will probably occur in middleware or upper layer applications. To prevent unexpected consequences, you are advised to use CBR to back up ECSs. Then, use idle servers to simulate the production environment and test-fix the vulnerability. If the test-fix succeeds, fix the vulnerability on servers running in the production environment.

  • Servers need to access the Internet and use external image sources to fix vulnerabilities.

Urgency

  • High: This vulnerability must be fixed as soon as possible. Attackers may exploit this vulnerability to damage the server.

  • Medium: You are advised to fix the vulnerability to enhance your server security.

  • Safe for now: This vulnerability has a small threat to server security. You can choose to fix or ignore it.

Vulnerability Fix Priority

Vulnerabilities detected by HSS are classified into four priority levels: critical, high, medium, and low. You can refer to the priorities to fix the vulnerabilities that have significant impact on your server first.

  • Critical: This vulnerability must be fixed immediately. Attackers may exploit this vulnerability to cause great damage to the server.

  • High: This vulnerability must be fixed as soon as possible. Attackers may exploit this vulnerability to damage the server.

  • Medium: You are advised to fix the vulnerability to enhance your server security.

  • Low: This vulnerability has a small threat to server security. You can choose to fix or ignore it.

Vulnerability Display

Detected vulnerabilities will be displayed in the vulnerability list for seven days, regardless of whether you have handled them.

Automatically Fixing Vulnerabilities (Vulnerability View)

You can only fix Linux and Windows vulnerabilities with one-click on the console.

Note

A maximum of 1,000 server vulnerabilities can be fixed at a time. If there are more than 1,000 vulnerabilities, fix them in batches.

  1. Log in to the management console.

  2. In the navigation pane, choose Prediction > Vulnerabilities.

  3. Fix Linux and Windows vulnerabilities.

    • Fixing a single vulnerability

      Locate the row containing a target vulnerability and click Fix in the Operation column.

    • Fixing multiple vulnerabilities

      Select all target vulnerabilities and click Fix in the upper left corner of the vulnerability list to fix vulnerabilities in batches.

    • Fix all vulnerabilities.

      Click Fix in the upper left corner of the vulnerability list to fix all vulnerabilities.

    • Fix one or more servers affected by a vulnerability.

      1. Click a vulnerability name.

      2. On the vulnerability details slide-out panel displayed, click the Affected tab, locate the row containing the target server, and click Fix in the Operation column.

        You can also select all target servers and click Fix above the server list to fix vulnerabilities for the servers in batches.

  1. In the displayed dialog box, confirm the number of vulnerabilities to be fixed and the number of affected assets.

    For Linux vulnerabilities, you can click View details in the Fix dialog box to view the name of the component to be fixed.

  2. In the Fix dialog box displayed, select I am aware that if I have not backed up my ECSs before fixing vulnerabilities, services may be interrupted and fail to be rolled back during maintenance. and click Auto Fix.

  3. Click a vulnerability name.

  4. Click the Handling History tab to view the fix status of the target vulnerability in the Status column. Table 2 describes vulnerability fix statuses.

    Table 2 Vulnerability fix statuses

    Status

    Description

    Unhandled

    The vulnerability is not fixed.

    Ignored

    The vulnerability does not affect your services. You have ignored the vulnerability.

    Verifying

    HSS is verifying whether a fixed vulnerability is successfully fixed.

    Fixing

    HSS is fixing the vulnerability.

    Fixed

    The vulnerability has been successfully fixed.

    Restart required

    The vulnerability has been successfully fixed. You need to restart the server as soon as possible.

    Failed

    The vulnerability fails to be fixed. The possible cause is that the vulnerability does not exist or has been changed.

    Restart the server and try again

    This status is displayed only for vulnerabilities that exist on Windows servers.

    The vulnerability has not been fixed on the Windows server for a long time. As a result, the latest patch cannot be installed. You need to install an earlier patch, restart the server, and then install the latest patch.

Automatically Fixing Vulnerabilities (Server View)

You can only fix Linux and Windows vulnerabilities with one-click on the console.

  1. Log in to the management console.

  2. In the navigation pane, choose Prediction > Vulnerabilities.

  3. Fix Linux and Windows vulnerabilities.

    • Fixing all Linux or Windows vulnerabilities on a server

      1. Locate the row containing a target server and click Fix in the Operation column.

        You can also select multiple servers and click Fix in the upper part of the vulnerability list. To fix all server vulnerabilities, you can select all servers in the batch fix dialog box.

      2. In the displayed dialog box, confirm the number of vulnerabilities to be fixed and the number of affected assets.

        For Linux vulnerabilities, you can view fix commands in the dialog box to view the name of the component to be fixed.

      3. In the Fix dialog box displayed, select the type of the vulnerability to be fixed, select I am aware that if I have not backed up my ECSs before fixing vulnerabilities, services may be interrupted and fail to be rolled back during maintenance., and click OK.

        Only Linux and Windows vulnerabilities can be automatically fixed with one-click. Web-CMS and application vulnerabilities need to be manually fixed by logging in to the server.

      4. Click the server name. On the server details slide-out panel displayed, view the vulnerability fix status. Table 3 describes vulnerability fix statuses.

    • Fixing one or more vulnerabilities on a server

      1. Click the name of a target server. The server details slide-out panel is displayed.

      2. Locate the row containing a target vulnerability and click Fix in the Operation column.

        Alternatively, you can select all target vulnerabilities and click Fix above the vulnerability list to fix vulnerabilities in batches.

      3. In the displayed dialog box, confirm the number of vulnerabilities to be fixed and the number of affected assets.

        For Linux vulnerabilities, you can view fix commands in the dialog box to view the name of the component to be fixed.

      4. In the Fix dialog box displayed, select I am aware that if I have not backed up my ECSs before fixing vulnerabilities, services may be interrupted and fail to be rolled back during maintenance., and click Auto Fix.

      5. In the Status column of the target vulnerability, view the fix status of the vulnerability. Table 3 describes vulnerability fix statuses.

    Table 3 Vulnerability fix statuses

    Status

    Description

    Unhandled

    The vulnerability is not fixed.

    Ignored

    The vulnerability does not affect your services. You have ignored the vulnerability.

    Verifying

    HSS is verifying whether a fixed vulnerability is successfully fixed.

    Fixing

    HSS is fixing the vulnerability.

    Fixed

    The vulnerability has been successfully fixed.

    Restart required

    The vulnerability has been successfully fixed. You need to restart the server as soon as possible.

    Failed

    The vulnerability fails to be fixed. The possible cause is that the vulnerability does not exist or has been changed.

    Restart the server and try again

    This status is displayed only for vulnerabilities that exist on Windows servers.

    The vulnerability has not been fixed on the Windows server for a long time. As a result, the latest patch cannot be installed. You need to install an earlier patch, restart the server, and then install the latest patch.

Manually Fixing Vulnerabilities

HSS cannot automatically fix Web-CMS vulnerabilities, application vulnerabilities, and emergency vulnerabilities in one click. You can log in to the server to manually fix them by referring to the fix suggestions on the vulnerability details slide-out panel.

Note

  • Restart the system after you fixed a Windows OS or Linux kernel vulnerability, or HSS will probably continue to warn you of this vulnerability.

  • Fix the vulnerabilities in sequence based on the suggestions.

  • If multiple software packages on the same server have the same vulnerability, you only need to fix the vulnerability once.

Viewing vulnerability fix suggestions

  1. Log in to the management console.

  2. In the navigation pane, choose Prediction > Vulnerabilities.

  3. Click the name of a target vulnerability to access the vulnerability details slide-out panel and view the fix suggestions.

Fixing vulnerabilities by referring to vulnerability fix suggestions

Vulnerability fix may affect service stability. You are advised to use either of the following methods to avoid such impact:

  • Method 1: Create a new VM to fix the vulnerability.

    1. Create an image for the ECS to be fixed.

    2. Use the image to create an ECS.

    3. Fix the vulnerability on the new ECS and verify the result.

    4. Switch services over to the new ECS and verify they are stably running.

    5. Release the original ECS. If a fault occurs after the service switchover and cannot be rectified, you can switch services back to the original ECS.

  • Method 2: Fix the vulnerability on the target server.

    1. Create a backup for the ECS whose vulnerabilities need to be fixed.

    2. Fix vulnerabilities on the current server.

    3. If services become unavailable after the vulnerability is fixed and cannot be recovered in a timely manner, use the backup to restore the server.

    Note

    • Use method 1 if you are fixing a vulnerability for the first time and cannot estimate impact on services. In this way, you can release the ECS at any time to save costs if the vulnerability fails to be fixed.

    • Use method 2 if you have fixed the vulnerability on similar servers before.

Ignoring a Vulnerability

Some vulnerabilities are risky only in specific conditions. For example, if a vulnerability can be exploited only through an open port, but the target server does not open any ports, the vulnerability will not harm the server. Such vulnerabilities can be ignored. HSS will not generate alarms for ignored vulnerabilities.

  1. Log in to the management console.

  2. In the navigation pane, choose Prediction > Vulnerabilities.

  3. Locate the row containing a target vulnerability and click Ignore in the Operation column.

  4. In the dialog box displayed, click OK.

Whitelisting Vulnerabilities

If you evaluate that some vulnerabilities do not affect your services and do not want to view the vulnerabilities in the vulnerability list, you can whitelist the vulnerabilities. After they are whitelisted, the vulnerabilities will be ignored in the vulnerability list and no alarms will be reported. The vulnerabilities will not be scanned and the vulnerability information will not be displayed when the next vulnerability scan task is executed.

  1. Log in to the management console.

  2. In the navigation pane, choose Prediction > Vulnerabilities.

    • Whitelisting all servers that are affected by a vulnerability

      HSS will ignore the vulnerability when scanning for vulnerabilities on all servers.

      1. In the Operation column of the row containing the target vulnerability, click More and select Add to Whitelist.

        You can also select multiple vulnerabilities and click Add to Whitelist above the vulnerability list.

        **Figure 1** Whitelisting all servers that are affected by a vulnerability

        Figure 1 Whitelisting all servers that are affected by a vulnerability

      2. In the dialog box displayed, click OK.

    • Whitelisting one or more servers that are affected by a vulnerability

      HSS will ignore the vulnerability when scanning for vulnerabilities on these servers.

      1. Click a target vulnerability name.

      2. On the slide-out panel displayed, click the Affected tab.

      3. In the Operation column of the row containing the target server, click More and select Add to Whitelist.

        You can also select multiple servers and click Add to Whitelist above the server list.

        **Figure 2** Whitelisting a single server that is affected by a vulnerability

        Figure 2 Whitelisting a single server that is affected by a vulnerability

      4. In the dialog box displayed, click OK.

    • Whitelisting vulnerabilities using whitelist rules

      1. In the upper right corner of the Vulnerabilities page, click Configure Policy. The Configure Policy slide-out panel is displayed.

      2. In the Vulnerability Whitelist area, click Add Rule.

      3. Configure a whitelist rule according to Table 4.

        **Figure 3** Configuring a whitelist rule

        Figure 3 Configuring a whitelist rule

        Table 4 Vulnerability whitelist rule parameters

        Parameter

        Description

        Type

        Select the type of vulnerabilities to be whitelisted. Possible values are as follows:

        • Linux Vulnerabilities

        • Windows Vulnerabilities

        • Web-CMS Vulnerabilities

        • Application Vulnerabilities

        • Emergency Vulnerabilities

        Vulnerability

        Select one or more vulnerabilities to be whitelisted.

        Rule Scope

        Select the servers affected by the vulnerabilities. Possible values are as follows:

        • All servers

          HSS will ignore the vulnerability when scanning for vulnerabilities on all servers.

        • Selected servers

          Select one or more target servers. HSS will ignore the vulnerabilities when scanning for vulnerabilities on these servers.

          You can search for a target server by server name, ID, EIP, or private IP address.

        Remarks (Optional)

        Enter the remarks.

      4. Click OK.

Verifying the Vulnerability Fix

After you manually fix vulnerabilities, you are advised to verify the fixing result.

  • Method 1: On the vulnerability details page, click Verify to perform one-click verification.

    Note

    • The fixing of emergency vulnerabilities cannot be verified.

    • Only application vulnerabilities of the JAR package can be verified. Application vulnerabilities of the non-JAR package are automatically filtered out and not verified.

  • Method 2: Ensure the software has been upgraded to the latest version. The following table provides the commands to check the software upgrade result.

    Table 5 Verification commands

    OS

    Verification Command

    CentOS/Fedora /Euler/Red Hat/Oracle

    rpm -qa | grep Software_name

    Debian/Ubuntu

    dpkg -l | grep Software_name

    Gentoo

    emerge --search Software_name